#include<iostream>
#include<math.h>
#include<string>
using namespace std;

int main(){
	string h;
	string strs;
	getline(cin, h);
	int number = 1;
	int n = h.size();
	for (int i = 0; i < n; i++){
		char s = h.at(i);
		strs = s;
		if (strs == "L"){
			number *= 2;
		}
		else{
			number = 2*number+1;
		}

	}

	cout << number << endl;
	return 0;
}